Hydrofluorocarbon (HFC) products are widely utilized in many applications, including refrigeration, air conditioning, foam expansion, and as propellants for aerosol products including medical aerosol devices. Although HFC's have proven to be more climate friendly than the chlorofluorocarbon and hydrochlorofluorocarbon products that they replaced, it has now been discovered that they exhibit an appreciable global warming potential (GWP).
The search for more acceptable alternatives to current fluorocarbon products has led to the emergence of hydrofluoroolefin (HFO) products. Relative to their predecessors, HFOs are expected to exert less impact on the atmosphere in the form of a lesser, or no, detrimental impact on the ozone layer and their much lower GWP as compared to HFC's. Advantageously, HFO's also exhibit low flammability and low toxicity.
As the environmental, and thus, economic importance of HFO's has developed, so has the demand for precursors utilized in their production. Many desirable HFO compounds, e.g., such as 2,3,3,3-tetrafluoroprop-1-ene or 1,3,3,3-tetrafluoroprop-1-ene, may typically be produced utilizing feedstocks of chlorocarbons, and in particular, chlorinated propenes, which may also find use as feedstocks for the manufacture of polyurethane blowing agents, biocides and polymers.
Unfortunately, many chlorinated propenes may have limited commercial availability, and/or may only be available at prohibitively high cost, due at least in part to the suboptimal processes typically utilized in their manufacture. Conventional processes for the manufacture of chlorinated propenes may typically involve multiple chlorination procedures on less substituted propane precursors, which may require the use of extreme operating conditions and/or expensive catalysts or reagents. Even if such conditions, catalysts and/or reagents are utilized, many conventional processes for the production of chlorinated propenes may yet suffer from low selectivity and/or low yield. Any of these alone, much less all of them combined, can render the conventional production of chlorinated propenes prohibitively expensive on the large scale required to be useful as feedstocks for the production of downstream products.
It would thus be desirable to provide improved processes for the production of chlorocarbon precursors useful as feedstocks in the synthesis of refrigerants and other commercial products. More particularly, such processes would provide an improvement over the current state of the art if they were less costly in starting materials, while yet providing higher selectivity and/or yield.